Abstract
We show that it is possible to still use semiclassical gravity together with quantum field theory beyond the regimes where the field state is coherent. In particular, we identify families of cat states (superposition of almost-distinguishable coherent states that have very non-classical features) for which the gravitational backreaction can be modeled by semiclassical gravity.
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Acknowledgments
The authors thank Albert Roura for very insightful discussions during RQI-N 2023. Research at Perimeter Institute is supported in part by the Government of Canada through the Department of Innovation, Science and Economic Development Canada and by the Province of Ontario through the Ministry of Colleges and Universities. E. M-M. is funded by the NSERC Discovery program as well as his Ontario Early Researcher Award.
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Ahmed, S., Lima, C. & Martín-Martínez, E. Semiclassical gravity beyond coherent states. J. High Energ. Phys. 2024, 1 (2024). https://doi.org/10.1007/JHEP01(2024)001
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DOI: https://doi.org/10.1007/JHEP01(2024)001